The present invention relates to a method of and an apparatus for manufacturing a vehicle wheel. More specifically, the present invention relates to a process and apparatus for securing a spider to a wheel rim.
Two piece vehicle wheels include an annular wheel rim, which is adapted to carry a pneumatic tire, and a disc-like spider. A "spider" can be defined as the beauty face of an auto wheel inside the wheel rim or as the center dish or hub of a truck or other vehicle wheel. It has sometimes been termed a wheel disk. A spider is typically formed across an end of the wheel rim. Alternatively, the spider can be recessed within the wheel rim. The spider includes a wheel hub having a central pilot hole and a plurality of wheel stud holes formed therethrough for mounting the wheel upon a vehicle. Typically, the spider also includes a plurality of wheel spokes connecting the wheel hub to the wheel rim.
Vehicle wheels have usually been produced in one piece by methods such as casting or forging. They have also been produced in two or three pieces. In this method, either a one or a two piece rim is joined to a one piece spider by welding, bolting or riveting. All of these known processes are time consuming and fairly expensive. Welding is disadvantageous because it results in a reduced material condition in the heat affected zone. Bolting or riveting is disadvantageous because non-uniform stress distributions are introduced at the annular joint between the wheel rim and the spider.
Manufacturers have, therefore, begun casting vehicle wheel spiders and forming the rim by spinning the rim from the spider to make a one piece wheel. This process is, unfortunately, time consuming and expensive. In addition, cast wheels are relatively porous and thus have a tendency to leak when a tire without an inner tube is mounted thereon. Also, they are not as shiny as the owners of the vehicles desire their wheels to be. The industry is currently producing most one piece cast rims and two piece rims with a cast spider welded to a rim section formed by methods other than casting.
Known two piece wheels are formed from metals such as steel, aluminum, magnesium, titanium or alloys thereof. Also, it is known that the spider can be formed from a different material than is the wheel rim.
The use of friction welding is known in the wheel industry. Thus, it is known that a wheel rim can be formed by e.g. casting or forging and the spider, which is similarly formed, can be connected to the rim by means of a friction weld. Similarly, it is known that wheel rims and spiders can be connected together by electromagnetic forming or by other related high velocity forming techniques. However, each of these techniques have their disadvantages. In light of the problems with conventional vehicle wheel manufacturing methods, as mentioned above, a need exists for better manufacturing processes for wheels.
Accordingly, it has been considered desirable to develop a new and improved method of manufacturing a wheel and an apparatus therefor which would overcome the foregoing difficulties and others while providing better and more advantageous overall results.